<!doctype html>
<head>
<meta charset="utf-8">
<title></title>
</head>

<body>
<?php  
$arr[1] = 1; 
for($i = 2;$i < 21;$i++) 
	{     
		$arr[$i] = $arr[$i-1] + $arr[$i-2]; } 
		echo join(",",$arr);
?>  

</body>
</html>
